package com.hzdracom.zhangnn.gradientviewdemo;

import android.graphics.Color;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;

import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    /**
     * The {@link android.support.v4.view.PagerAdapter} that will provide
     * fragments for each of the sections. We use a
     * {@link FragmentPagerAdapter} derivative, which will keep every
     * loaded fragment in memory. If this becomes too memory intensive, it
     * may be best to switch to a
     * {@link android.support.v4.app.FragmentStatePagerAdapter}.
     */
    private SectionsPagerAdapter mSectionsPagerAdapter;

    /**
     * The {@link ViewPager} that will host the section contents.
     */
    private ViewPager mViewPager;
    private GradientIconView tabOne;
    private GradientIconView tabTwo;
    private GradientIconView tabThree;
    private GradientIconView tabFour;
    private ArrayList<GradientIconView> viewList = new ArrayList<>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Create the adapter that will return a fragment for each of the three
        // primary sections of the activity.
        mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

        // Set up the ViewPager with the sections adapter.
        mViewPager = (ViewPager) findViewById(R.id.container);
        mViewPager.setAdapter(mSectionsPagerAdapter);

        tabOne = (GradientIconView) findViewById(R.id.tab1);
        tabTwo = (GradientIconView) findViewById(R.id.tab2);
        tabThree = (GradientIconView) findViewById(R.id.tab3);
        tabFour = (GradientIconView) findViewById(R.id.tab4);

//        tabOne.setTextSize(12);
//        tabTwo.setTextSize(12);
//        tabThree.setTextSize(12);
//        tabFour.setTextSize(12);

        viewList.add(tabOne);
        viewList.add(tabTwo);
        viewList.add(tabThree);
        viewList.add(tabFour);
        tabOne.setOnClickListener(this);
        tabTwo.setOnClickListener(this);
        tabThree.setOnClickListener(this);
        tabFour.setOnClickListener(this);
        mViewPager.addOnPageChangeListener(new ZHANG());
        mViewPager.setCurrentItem(0);
        viewList.get(0).setViewAlpha(1);
        tabThree.setIconMarginTop(6);
        tabFour.setIconMarginTop(6);
        tabThree.setTextMarginBottom(4);
        tabFour.setTextMarginBottom(4);
//        float x = this.getResources().getDisplayMetrics().density;
//        float y = this.getResources().getDisplayMetrics().densityDpi;
//        float z = this.getResources().getDisplayMetrics().scaledDensity;
    }

    /**
     * 重置其他的Tab text
     */
    private void resetOtherTabs() {
        for (int i = 0; i < viewList.size(); i++) {
            viewList.get(i).setViewAlpha(0);
        }
    }

    @Override
    public void onClick(View v) {
        resetOtherTabs();
        switch (v.getId()) {
            case R.id.tab1:
                viewList.get(0).setViewAlpha(1.0f);
                mViewPager.setCurrentItem(0, false);
                break;
            case R.id.tab2:
                viewList.get(1).setViewAlpha(1.0f);
                mViewPager.setCurrentItem(1, false);
                break;
            case R.id.tab3:
                viewList.get(2).setViewAlpha(1.0f);
                mViewPager.setCurrentItem(2, false);
                break;
            case R.id.tab4:
                viewList.get(3).setViewAlpha(1.0f);
                mViewPager.setCurrentItem(3, false);
                break;
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    private class ZHANG implements ViewPager.OnPageChangeListener {

        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
            if (positionOffset > 0) {
                GradientIconView left = viewList.get(position);
                GradientIconView right = viewList.get(position + 1);

                left.setViewAlpha(1 - positionOffset);
                right.setViewAlpha(positionOffset);
            }
        }

        @Override
        public void onPageSelected(int position) {

        }

        @Override
        public void onPageScrollStateChanged(int state) {

        }
    }


    public static class PlaceholderFragment extends Fragment {
        /**
         * The fragment argument representing the section number for this
         * fragment.
         */
        private static final String ARG_SECTION_NUMBER = "section_number";

        public PlaceholderFragment() {
        }

        /**
         * Returns a new instance of this fragment for the given section
         * number.
         */
        public static PlaceholderFragment newInstance(int sectionNumber) {
            PlaceholderFragment fragment = new PlaceholderFragment();
            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main, container, false);
            TextView textView = (TextView) rootView.findViewById(R.id.section_label);
            textView.setText(getString(R.string.section_format, getArguments().getInt(ARG_SECTION_NUMBER)));
            return rootView;
        }
    }

    /**
     * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
     * one of the sections/tabs/pages.
     */
    public class SectionsPagerAdapter extends FragmentPagerAdapter {

        public SectionsPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int position) {
            // getItem is called to instantiate the fragment for the given page.
            // Return a PlaceholderFragment (defined as a static inner class below).
            return PlaceholderFragment.newInstance(position + 1);
        }

        @Override
        public int getCount() {
            // Show 3 total pages.
            return 4;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            switch (position) {
                case 0:
                    return "SECTION 1";
                case 1:
                    return "SECTION 2";
                case 2:
                    return "SECTION 3";
                case 3:
                    return "SECTION 4";

            }
            return null;
        }
    }
}
